Electronics Repair FAQ & Testimonials- Part 29


can i  replace the diode (RL-205) with (RL-207)
because i our area  RL205 is not available and  RL207 has 1000 peak reverse voltage while RL-205 has 600 peak reverse coltage…..
please replay me

R.mohammed ali

Hi Mohammed,

If the ampere is the same yes you can replace it.



Hi ! Jestine first of all I would like to thanks for which you was sending last time.in this week I was test sony tv the problem of it’s on power supply board .The problem of it’s as follows :, fuse , resistor 470 k ohm and power regulator transistor c3550 blowed (birned) even though I have been got these problem I can’t repair becouse of power regulator transistor c3550 problem . the plame is I cant get it in the shop by it number, so can you tel me the equvalent of these transistor .

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Electronics Repair FAQ & Testimonials- Part 28


Jestine thanks for your reply. How can I check if the power supply is stable bcz I don’t have any oscilloscope meter,but I have a sanwa meter CX 506A where I can trace any defect in cap [ESR].I’ve already change all the cap in the ps.I’m sure that the ps is not ok but don’t know where is the culprit?
Thanks and regards…………..

Hi Bobby,

If you get the exact voltage from your meter and the needle did not move (constant) then you know you have a good and stable voltage.


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Electronics Repair FAQ & Testimonials-Part 26

Hi Jestine ,

Can i check with you ,  if i measure the VCC pin of the power ic UC3842 and i get the reading not constantly example 11.xx dcv jump to 14.xx dcv then go down to 12.xx dcv and then up again , normally which parts did i need to check . Thanks

HI Chong,

It can be the IC itself have problem, the supply vcc line e-cap ESR value have shoot up or even if there is components shorted in the secondary side preventing the ic to start up. I suggest that you check all secondary output diodes first and filer caps, then optoisolator ic then back to the power ic.  Sometimes corresponding components to the power ic also could have problem

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Electronics Repair FAQ And Testimonials- Part 25

Hi Jestine!

Good day!

Thanks a lot for your e-mail.

I’m so glad and happy to tell you that I have already repaired a number of electronic equipment with the help of your ebooks.
It’s not only profitable but the joy of self-achievement are wonderful.

Thanks again and I wish you and your family good health and more power to you on your career!

With my best regards,



What should new electronic technicians do
when they come across older electronic devices or equipment with obsolete components?
like for example
lets say you have a circuit board that was assemble in the early 1980s. the part that needs replacing is a transistor.
how many times does this old transistor
part number has to be cross referenced from the late 1980s, 1990s,2000 etc.
will the part number on that old transistor be in todays cross reference book?

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Electronics Repair FAQ And Testimonials- Part 24

HI Roland,

Good day Jestine,

Good day!

I would just like to inquire with regards to a burned varistor. I had a electronic control  board that has burned varistor and the part number was also

burned. Is there any way or technique that I can do to replace the burned varistor. i have measured the varistor and has a value of 27ohms which is i believe that is shorted and keeps on blowing the fuse.

Yes you are right by right it should not have any reading.

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